U.S. patent number 6,221,088 [Application Number 09/450,788] was granted by the patent office on 2001-04-24 for powered handpiece and surgical blades and methods thereof.
This patent grant is currently assigned to Xomed Surgical Products, Inc.. Invention is credited to F. Barry Bays.
United States Patent |
6,221,088 |
Bays |
April 24, 2001 |
Powered handpiece and surgical blades and methods thereof
Abstract
A powered handpiece for driving a surgical blade to cut
anatomical tissue includes a reusable handpiece body having a
distal end for being coupled with a surgical blade, a drive shaft
in the handpiece body for rotatably driving the surgical blade, a
motor assembly for being installed in the handpiece body to
rotatably drive the drive shaft and a suction channel in the
handpiece body including a portion extending through the drive
shaft parallel to a longitudinal axis of the motor assembly for
evacuating anatomical tissue cut by the blade from the handpiece
body for external collection. The surgical blade is for use with
the powered handpiece and carries a sealing arrangement
facilitating irrigation and suction. The handpiece body is capable
of being sterilized to medical standards prior to each use. The
motor assembly, which is non-sterile, is removable from the
handpiece body prior to sterilization of the handpiece body and is
reinstallable in the handpiece body subsequent to sterilization of
the handpiece body without contaminating the sterilized handpiece
body. An installation device includes a reusable funnel for being
disposed over the handpiece body and through which the motor
assembly is inserted for installation in the handpiece body. An
electric cord assembly for being coupled between the handpiece and
a power console includes a plug for being plugged into the motor
assembly after the motor assembly has been installed in the
handpiece body and a locking ring on the plug for selectively,
releasably, lockingly engaging the handpiece body to secure the
motor assembly in the handpiece body.
Inventors: |
Bays; F. Barry (Clearwater,
FL) |
Assignee: |
Xomed Surgical Products, Inc.
(Jacksonville, FL)
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Family
ID: |
27110033 |
Appl.
No.: |
09/450,788 |
Filed: |
November 30, 1999 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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005012 |
Jan 9, 1999 |
6010477 |
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775147 |
Dec 31, 1996 |
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719130 |
Sep 24, 1996 |
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Current U.S.
Class: |
606/170;
604/22 |
Current CPC
Class: |
A61B
17/32002 (20130101); A61M 1/84 (20210501); A61B
2217/005 (20130101); A61B 2217/007 (20130101); A61B
2090/0813 (20160201) |
Current International
Class: |
A61B
17/32 (20060101); A61M 1/00 (20060101); A61B
19/00 (20060101); A61B 017/20 () |
Field of
Search: |
;606/180,170,167
;604/22,35,43 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2362157 |
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Dec 1973 |
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DE |
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0310285 |
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Sep 1988 |
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EP |
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2093353 |
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Feb 1982 |
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GB |
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Other References
"Advanced Arthroscopic Surgical System Manual", Dyonics, Inc., 160
Dascomb Road, Andover, MA 01810, Jan. 23, 1985. .
"Beyond all others Advanced Arthroscopic Surgical System from
Dyonics", Dyonics, Inc., 160 Dascomb Road, Andover, MA 01810. .
Intra-Aro.TM. Drive System, Concept Incorporated, 12707 U.S. 19
South, Clearwater, Florida 33546. .
"The Elite Arthroscopy Power System", Stryker Endoscopy. .
"Total Arthroscopy System", Richard Wolf Medical Instruments Corp.,
7046 Lyndon Avenue Rosemont, Illinois 60018. .
"Introducing the Hall.RTM. Arthrotome.RTM. System High Speed
Handpiece" The Hall.RTM. Arthrotome.TM. System Instruction
Manual..
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Primary Examiner: Truong; Kevin
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of prior application Ser. No.
09/005,012 filed Jan. 9, 1999, now U.S. Pat. No. 6,010,477 which is
a divisional of prior application Ser. No. 08/775,147 filed Dec.
31, 1996 and now abandoned, which is a continuation-in-part of
prior application Ser. No. 08/719,130 filed Sep. 24, 1996 and now
abandoned, the disclosures of which are incorporated herein by
reference.
Claims
What is claimed is:
1. A surgical blade assembly for cutting anatomical tissue
comprising
an elongate outer tubular member having an open distal end, an open
proximal end and a lumen extending between said distal and proximal
ends, and an outer member hub secured to said proximal end, said
outer member hub having a configuration to be removably coupled to
a powered surgical handpiece whereby said outer member is rigidly
secured to the handpiece; and
an elongate inner member including an inner tube movably disposed
within said outer member and having a distal end for cutting
anatomical tissue when said inner tube is moved within said outer
member, a proximal end, a longitudinal axis and a lumen coaxial
with said axis and extending between said distal and proximal ends
of said inner tube, and an inner tube hub secured to said proximal
end of said inner member, said distal end of said inner member
being accessible to anatomical tissue via said open distal end of
said outer member, said inner member hub having a configuration to
be removably coupled to the powered surgical handpiece to be moved
relative to said outer member to move said inner tube to cut
anatomical tissue, said inner member hub having a passage coaxial
with said longitudinal axis and extending entirely through said
inner member hub, said inner member including a continuous suction
passage formed by said lumen and said passage of said inner member
hub, said suction passage extending, in its entirety, axially
through said inner member from said inner member distal end of said
inner tube through an open proximal end of said inner member hub
for removal of cut anatomical tissue from said open proximal end of
said inner member hub when said inner member hub is coupled to the
powered surgical handpiece.
2. A surgical blade assembly as recited in claim 1 wherein said
inner tube is rotatably disposed in said outer member.
3. A surgical blade assembly as recited in claim 2 wherein said
distal end of said outer tube is configured to cooperate with said
distal end of said inner member to effect a shearing action on
anatomical tissue.
4. A surgical blade assembly as recited in claim 1 wherein said
outer member hub includes an irrigation supply passage for
supplying irrigation fluid between said outer member and said inner
member to said distal end of said outer member.
5. A surgical blade assembly as recited in claim 4 and further
including a seal disposed in said outer member hub proximally of
said irrigation supply passage for preventing passage of irrigation
fluid proximally from said outer member hub.
6. A surgical blade assembly for cutting anatomical tissue
comprising
an elongate outer member having a distal end with an opening
therein, an open proximal end and a lumen therethrough
communicating with said opening and said open proximal end, and an
outer member hub coupled with said proximal end, said outer member
hub having a passage extending entirely therethrough in
communication with said lumen, said outer member hub including an
external flange for releasable, locking engagement with a powered
surgical handpiece; and
an elongate inner member including an inner tube extending through
said passage to be movably disposed in said lumen and having an
open distal end, an open proximal end extending proximally from
said outer member hub and a lumen communicating with said distal
end of said inner tube and said open proximal end of said inner
tube, and an inner member hub coupled with said proximal end of
said inner tube and disposed proximally of said outer member hub,
said distal end of said inner tube having a cutting edge exposed by
said opening in said distal end of said outer member for cutting
anatomical tissue when said inner tube is moved relative to said
outer member, said inner member hub including a plurality of
longitudinally extending prongs having slots therebetween for
releasable securement to a drive shaft of the powered surgical
handpiece, said inner member hub having a longitudinal passage
entirely therethrough in communication with said lumen of said
inner tube, said inner member including a continuous suction
passage formed by, said lumen of said inner tube and said passage,
in its entirety, through said inner member hub, said suction
passage extending from said distal end of said inner tube through a
proximal end of said inner member hub whereby debris due to cutting
is aspirated proximally from said proximal end of said inner member
hub when said inner member hub is secured to the drive shaft of the
powered surgical handpiece.
7. A surgical blade assembly as recited in claim 6 wherein said
inner tube is rotatably disposed in said outer member.
8. A surgical blade assembly as recited in claim 6 wherein said
cutting edge is aligned with said opening in said distal end of
said outer member.
9. A surgical blade assembly as recited in claim 8 wherein said
distal end of said outer member has a cutting edge cooperating with
said cutting edge of said inner tube to cut anatomical tissue.
10. A surgical blade assembly as recited in claim 6 wherein said
inner blade further includes a spring biased seal disposed distally
of said prongs for providing longitudinal tolerance between said
inner member and the drive shaft.
11. A surgical blade assembly as recited in claim 6 wherein said
prongs terminate proximally at tapered tips.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to powered handpieces for driving
surgical blades and, more particularly, to electric motor driven,
powered handpieces, surgical blade assemblies for use with such
handpieces, powered handpiece systems utilizing non-sterile
electric motors and methods for supplying powered handpieces for
use in surgery.
2. Brief Description of the Prior Art
Powered handpieces are commonly used in many medical specialities
to drive surgical blades for performing various diverse cutting
functions including resection, comminution, dissection,
debridement, shaving, drilling, pulverizing and shaping of
anatomical tissue. In the areas of ENT/Head/Neck surgery, powered
or motorized handpieces and systems have been proposed as
illustrated by the Stryker Hummer system of Stryker Endoscopy, San
Diego, Calif., the Apex System of Linvatec, Incorporated, Largo,
Fla., the PS 3500 and EP-1 Surgical Drive System of Dyonics, Inc.
of Andover, Mass. and the Wizard microdebrider system of Xomed,
Inc., Jacksonville, Fla. Conventional powered handpieces are
typically all metal and reusable in design with permanently
installed motors. Such handpieces are typically decontaminated and
sterilized for reuse by steam autoclave and/or soaking in a
disinfectant solution resulting in reduced reliability and/or life
of the motors due to the heating and cooling cycles and/or due to
moisture seepage. A further disadvantage of conventional powered
handpieces is that the motor of a handpiece cannot be replaced
prior to surgery with a different speed motor in accordance with
the procedure to be performed.
Conventional powered handpieces generally use suction to evacuate
anatomical tissue cut or excised by the blades. Powered handpieces
currently in use generally force the excised anatomical tissue to
follow a suction path with major or substantial bends or angles.
Accordingly, there is a tendency for the excised tissue to become
clogged in the handpieces thusly impairing operation of the
handpieces and compromising the surgical procedure.
Another drawback of some conventional powered handpieces is that
the handpieces can only be operated by a power console specifically
designed for the handpieces and not by a power consoles designed
for other manufacturer's handpieces. Such handpieces therefore
require a major investment in capital equipment for the associated
power console.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to
overcome the disadvantages of prior art powered or motorized
handpieces for driving surgical blades.
Another object of the present invention is to facilitate evacuation
of cut or excised anatomical tissue from the cutting tip of a
surgical blade and out of a powered handpiece for the blade.
A further object of the present invention is to avoid clogging of
excised tissue evacuated through a suction channel of a powered
handpiece for a surgical blade by reducing areas of turbulence in
the suction channel.
A still further object of the present invention is to evacuate cut
or excised anatomical tissue from a surgical blade through a
suction channel extending through a powered handpiece for the
blade, the suction channel having a portion extending through a
drive shaft for rotatably driving the blade with the channel
portion being parallel to a longitudinal axis of a motor in the
handpiece.
An additional object of the present invention is to increase the
reliability and/or life of an electric motor of a reusable powered
handpiece by providing a method of supplying a powered handpiece
for surgery including removing the electric motor from a body of
the handpiece prior to medically acceptable sterilization of the
handpiece body to medical standards and reinstalling the electric
motor in the sterilized handpiece body prior to reuse of the
handpiece.
The present invention has as a further object to utilize a
non-sterile motor in a reusable powered handpiece by removing the
non-sterile motor from a body of the handpiece prior to
sterilization of the handpiece body to medical standards and
reinstalling the non-sterile motor in the sterilized handpiece body
subsequent to sterilization without contaminating the sterilized
handpiece body.
The present invention has as an additional object to provide a
device for installing a non-sterile motor in driving engagement
with a drive unit in a sterile handpiece body without contaminating
the sterile handpiece body.
Additionally, the present invention has as an object to provide a
surgical blade assembly for use with a reusable powered handpiece
having a non-sterile motor removable from a body of the handpiece
prior to medically acceptable sterilization of the handpiece body
to medical standards and reinstallable in the handpiece body
subsequent to sterilization thereof.
Another object of the present invention is to provide a surgical
blade assembly for use with a reusable powered handpiece having a
suction channel extending through a drive shaft for rotatably
driving the blade, the drive shaft being driven by a motor disposed
parallel to the drive shaft.
Some of the advantages of the present invention are that diverse
non-sterile, electric motors are readily interchangeable with the
handpiece allowing an optimal motor to be selected in accordance
with procedural use, the handpiece is relatively lightweight,
compact and ergodynamically functional for use by surgeons in
various specialities and, in particular, the areas of ENT/Head/Neck
surgery, accurate alignment of the motor assembly with the drive
unit is assured during installation of the motor assembly in the
handpiece body, the motor assembly can be installed in the
handpiece body by operating personnel just prior to the surgical
case, the handpiece can be powered off of various conventional
power consoles, and various diverse blades are interchangeable with
the handpiece for performing various diverse functions.
These and other objects, advantages and benefits are realized with
the present invention as characterized in a powered handpiece
including a reusable handpiece body having a distal end for
releasably receiving a surgical blade, a drive unit in the
handpiece body including a drive shaft for driving the blade to cut
anatomical tissue, a motor assembly for being disposed in the
handpiece body for driving the drive unit and an electrical cord
assembly for being electrically coupled between the motor and a
power console. The handpiece body is capable of being medically
sterilized to medical standards, such as by steam autoclave, gas
sterilization and/or soaking, prior to each use. The motor assembly
is removable from the handpiece body prior to sterilization of the
handpiece body and is replaceable in the handpiece body subsequent
to sterilization thereof without contaminating the sterile
handpiece body. An installation device for inserting the motor
assembly in the sterilized handpiece body without contaminating the
sterilized handpiece body includes a funnel capable of being
sterilized to medical standards and having a flared head and a
tubular stem for being disposed over an open proximal end of the
handpiece body. The motor assembly is inserted through the funnel
into the open proximal end of the handpiece body without impairing
the sterility of the handpiece body. In order to insure that the
motor assembly is inserted in the handpiece body in driving
engagement with the drive unit, an alignment mechanism is provided
including a slot or keyway in the proximal end of the handpiece
body and a protrusion or key on the motor assembly for being
received in the slot; and, when the key of the motor assembly is
received in the keyway of the handpiece body, the motor assembly
will be in driving engagement with the drive unit. The funnel
includes a protrusion or key for being received in the keyway of
the handpiece when the funnel is disposed over the handpiece body.
A notch is disposed in the funnel in longitudinal alignment with
the key of the funnel and, therefore, with the keyway of the
handpiece. The key of the motor assembly and the key of the funnel
can be received simultaneously in the keyway such that the key of
the motor assembly is passed through the notch into the keyway when
being inserted through the funnel to insure proper alignment of the
motor assembly with the drive unit. Once the motor assembly is
properly installed in the handpiece body, the funnel is removed and
the electrical cord assembly is coupled between the motor assembly
and, therefore, the handpiece body, and a power console. The
electrical cord assembly, which is capable of being sterilized to
medical standards for reuse, includes a first plug for being
electrically coupled with an electrical connector of the motor
assembly and a second plug for being electrically coupled with a
power console. The first plug carries a locking ring selectively
movable into locking engagement with the proximal end of the
handpiece body to secure the motor assembly therein. A surgical
blade assembly for use with the powered handpiece according to the
present invention includes an elongate outer tubular blade having a
distal cutting end, a hub mounting a proximal end of the outer
blade, an elongate inner tubular blade having a distal cutting end
for cooperating with the cutting end of the outer blade to cut
anatomical tissue, and a hub mounting a proximal end of the inner
blade. The inner blade is concentrically disposed in the outer
blade with the inner blade passing through the hub of the outer
blade. The hubs of the outer and inner blades are releasably
coupled with the distal end of the handpiece body with the inner
blade in driving engagement with the drive shaft. The handpiece
body includes a substantially straight suction channel for
evacuating tissue cut by the blades through the handpiece body for
external collection. The suction channel includes a portion
extending through the drive shaft parallel to a longitudinal axis
of the motor assembly.
Other objects and advantages of the present invention will become
apparent from the following description of the preferred
embodiments taken in conjunction with the accompanying drawings,
wherein like parts in each of the several figures are identified by
the same reference characters.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a powered handpiece according to
the present invention.
FIG. 2 is an exploded view, partly in section, of the powered
handpiece according to the present invention.
FIG. 3 is a side sectional view of a collet assembly of the powered
handpiece.
FIG. 4 is a side sectional view of a transfer hub assembly of the
powered handpiece.
FIG. 5 is a side view, partly in section, of a front drive shaft of
a drive unit disposed in the transfer hub assembly.
FIG. 6 is a side view, partly in section, of a rear drive shaft of
the drive unit.
FIG. 7 is a top view of the rear drive shaft.
FIG. 8. is a broken side view of a distal portion of a motor
assembly of the handpiece.
FIG. 9 is a broken side view, partly in section, of a proximal
portion of the motor assembly.
FIG. 10 is a side view of an electrical connector of the motor
assembly.
FIG. 11 is a proximal end view of the electrical connector.
FIG. 12 is a distal end view of the electrical connector.
FIG. 13 is a broken side view, partly in section, of an electrical
cable assembly of the powered handpiece connected between a body of
the handpiece and a power console.
FIG. 14 is a broken perspective view of a plug of the electrical
cable assembly for mating with the electrical connector.
FIG. 15 is a side sectional view of an installation device for
installing the motor assembly in the body of the handpiece.
FIG. 16 is a rearward end view of the installation device.
FIG. 17 is a forward end view of the installation device.
FIG. 18 is a fragmentary view, partly in section, of the
installation device.
FIG. 19 is a broken, exploded perspective view of the installation
device.
FIG. 20 is a broken side view of a blade assembly for use with the
powered handpiece according to the present invention.
FIG. 21 is a side sectional view of a hub of an outer blade of the
blade assembly.
FIG. 22 is a broken side view, partly in section, of an inner blade
and hub of the blade assembly.
FIG. 23 is an end view of the hub of the inner blade.
FIG. 24 is a side sectional view of a seal for the hub of the inner
blade.
FIG. 25 is a sectional view of an alternative seal for the drive
unit of the powered handpiece.
FIG. 26 is a side view, partly in section, illustrating a lip seal
for the drive unit of the powered handpiece.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A powered surgical handpiece 10 according to the present invention
is illustrated in FIGS. 1 and 2 and includes a handpiece body 12
and a motor assembly 14 for being removably installed in handpiece
body 12. The handpiece body 12 includes a collet assembly 16, a
transfer hub assembly 18 and a motor enclosure 20. Collet assembly
16, as shown in FIG. 3, is designed to releasably couple a desired
surgical blade to the handpiece body and includes an outer collet
member 22, a middle collet member 24 and an inner collet member 26.
Outer collet member 22, which is preferably made of stainless
steel, is hollow and has a cylindrical rearward section 28 mounted
to a forward end of transfer hub assembly 18 and a cylindrical
forward section 30 extending distally from rearward section 28 in
longitudinal or axial alignment therewith to terminate at a
peripheral edge. Rearward section 28 has a uniform external
diameter, smaller than a uniform external diameter of forward
section 30, except for a distal portion of the rearward section 28
which is flared or of increasing external diameter in the distal
direction to merge with the external diameter of the forward
section 30. A plurality of longitudinally extending grooves or
recesses 31 are formed in an external surface of the wall forming
rearward section 28, the grooves 31 being of the same length and
extending part way through the thickness of the rearward section
wall. Grooves 31, which extend parallel to a longitudinal axis of
the outer collet member 22, are juxtaposed to be laterally aligned
with one another with little or no space between lateral or side
edges of adjacent grooves 31 as shown in FIG. 1. A plurality of
longitudinally extending grooves or recesses 32, similar to grooves
31, are formed in an external surface of the wall forming forward
section 30 to extend part way through the thickness of the forward
section wall. Grooves 32 extend parallel to the longitudinal axis
of the outer collet member 22 and are juxtaposed to be laterally
aligned with one another. The grooves 32 are laterally juxtaposed
with a space between lateral or side edges of adjacent grooves 32
that is greater than the space between the side edges of grooves 31
as shown in FIG. 1. Grooves 32 are of the same length except for
grooves 32', spaced 90.degree. from one another about the
longitudinal axis of outer collet member 22, which-have a length
less than the length of the remaining grooves 32. Set screws 33 are
received in holes formed through the thickness of the forward
section wall distally of and in longitudinal alignment with grooves
32', respectively, with the set screws 33 disposed proximally of
distal ends of the remaining grooves 32. The grooves 31 and 32 have
rounded distal and proximal ends and serve to facilitate grasping
of the handpiece body 12. Outer collet member 22 has a lumen or
internal passage extending entirely therethrough with the rearward
section 28 defining a rearward passage section of uniform diameter
or cross-section, and the forward section 30 defining a forward
passage section of uniform diameter or cross-section larger than
the diameter or cross-section of the rearward passage section. The
rearward section wall is of increased thickness along the distal
portion of the rearward section 28 to define an internal shoulder
34 extending transverse to the longitudinal axis of the outer
collet member 22 at the junction of the rearward passage section
with the forward passage section. The set screws 33 protrude
inwardly into the forward passage section.
Middle collet member 24, which is preferably made of stainless
steel, is hollow and includes a tubular stem 35 terminating
proximally at an outwardly protruding, transverse flange 36 and
includes a cylindrical front end 37 extending longitudinally,
distally from the stem 35 in longitudinal or axial alignment
therewith to terminate distally at a tapered nose 38. The external
diameter of stem 35 is smaller than the external diameter of front
end 37 such that an external, transverse shoulder 39 is formed at
the junction of front end 37 with stem 35. The front end 37 and the
flange 36 have the same external diameter, which is selected to be
closely received in the forward section 30 of the outer collet
member 22 while allowing the middle collet member 24 to move
longitudinally relative to the outer collet member. Nose 38 defines
an annular rim 40, larger in external diameter than front end 37,
tapering to a transverse planar end wall 41. A plurality of
radially extending grooves or recesses 42 are formed in the
truncated conical external surface of nose 38 to facilitate
grasping of the middle collet member 24. A lumen or internal
passage extends entirely through the middle collet member 24 and
includes a rearward passage segment of uniform diameter or
cross-section extending through stem 35 and part way into front end
37, an intermediate passage segment of increasing diameter or
cross-section extending distally from the rearward passage segment
and a forward passage segment of uniform diameter or cross-section
extending distally from the intermediate passage segment to
terminate at an inner face of end wall 41. The forward,
intermediate and rearward passage segments are longitudinally or
axially aligned with one another, and the interior surface of the
front end 37 is angled along the intermediate passage segment to
define an internal sloping shoulder 43 between the forward and
rearward passage segments. The end wall 41 has an opening or
aperture 44 therein longitudinally or axially aligned with the
internal passage of middle collet member 24 and establishing
communication with the forward passage segment from externally of
the handpiece body 12.
Inner collet member 26 is preferably made of stainless steel and
comprises an elongate, hollow cylindrical or tubular member of
uniform external diameter defined by a wall of uniform thickness
along a distal portion of the cylindrical member and of uniform
greater thickness along the remainder of the cylindrical member to
form an internal transverse shoulder 45. A lumen or internal
passage is defined entirely through the inner collet member 26 and
includes a rearward passage portion of uniform diameter or
cross-section and a forward passage portion of uniform diameter or
cross-section, larger than the uniform diameter or cross-section of
the rearward passage portion, with the shoulder 45 being disposed
at the junction of the forward and rearward passage portions. A
plurality of semi-spherical holes 46 are formed through the wall of
the distal portion of the inner collet member 26 at 120.degree.
spaced locations about a longitudinal axis of the inner collet
member 26 with the holes 46 communicating with the forward passage
portion. A spherical ball bearing 47, is disposed in each hole 46
such that the ball bearings 47 protrude externally beyond an
external surface of the inner collet member 26 and protrude
internally beyond an internal surface of the inner collet member to
protrude into the forward passage portion while being prevented
from passing through the holes 46 into the forward passage portion.
The inner collet member 26 has an external diameter or size to be
closely received in the rearward passage section of the outer
collet member 22 with the external surface of the inner collet
member in contact with an internal surface of the outer collet
member.
Middle collet member 24 is assembled to the outer collet member 22
in concentric or coaxial arrangement with stem 35 disposed in the
forward passage section of the outer collet member 22 and flange 36
disposed proximally of set screws 33. The distance that set screws
33 protrude inwardly into the forward passage section of outer
collet member 22 is the same as or slightly less than the height of
external shoulder 39. The inner collet member 26 is concentrically
or coaxially disposed in the outer collet member 22 with a proximal
end of the inner collet member 26 fixedly secured, such as with
adhesive, in rearward section 28 such that a distal end of the
inner collet member 26 is disposed slightly distally of the distal
peripheral edge of the outer collet member 22. A helical coil
spring 48, preferably made of stainless steel, is concentrically
disposed around the inner collet member 26 and is mounted in
compression between internal shoulder 34 and flange 36 to bias the
middle collet member 24 longitudinally, distally relative to the
outer collet member 22 to an extended position as shown in FIGS. 2
and 3.
In the extended position, flange 36 is biased into abutment with
set screws 33, and external shoulder 39 is disposed slightly
proximally of the distal peripheral edge of outer collet member 22.
There is a small circumferential gap or space between the external
surface of the inner collet member 26 and an internal surface of
stem 35 such that the protruding ball bearings 47 are in contact
with the internal surface of stem 35 when the middle collet member
24 is in the extended position. Accordingly, the ball bearings 47
cannot move radially outwardly due to confinement by stem 35 and
cannot move inwardly through the holes 46. The middle collet member
24 is movable longitudinally, proximally relative to the outer
collet member 22 from the extended position to a retracted position
wherein the external shoulder 39 abuts the set screws 33 which
serve as a positive stop or abutment limiting proximal movement of
the middle collet member 24 in the retracted position. In the
retracted position, ball bearings 47 are no longer disposed in or
aligned with stem 35 but, rather, are disposed in or aligned with
the diametrically larger forward passage segment of front end 37
such that the ball bearings 47 can be moved radially outwardly by a
hub of a surgical blade introduced in inner collet member 26 via
aperture 44 as explained further below. Middle collet member 24 is
movable from the retracted position back to the extended position
due to the bias of spring 48 causing ball bearings 47 to again be
held in place in the holes 47 of the inner collet member 26.
Transfer hub assembly 18 is best illustrated in FIG. 4 and includes
a transfer body 49 mounted to the collet assembly 16 and a drive
unit 50 disposed in the transfer body 49 for driving a surgical
blade inserted in collet assembly 16. Transfer body 49 is
preferably made of titanium or stainless steel and includes a
distal cylindrical extension 51 and a proximal cylindrical
extension 52 longitudinally and laterally offset from and not
aligned with one another and a midsection 53 extending diagonally
or angularly between the distal and proximal cylindrical
extensions. A recess extends longitudinally in the distal extension
51 to terminate proximally at an end wall 54 in the midsection 53.
A recess extends longitudinally in the proximal extension 52 to
terminate distally at an end wall 55 in midsection 53, the end wall
55 being disposed distally of and parallel to end wall 54. The
distal and proximal extension recesses are parallel to one another
and are in communication with one another in midsection 53. A
tubular neck 56 extends longitudinally, distally from the distal
extension 51 in longitudinal or axial alignment therewith and has
an external diameter, smaller than the external diameter of the
distal extension, to be closely received in the rearward section 28
of the outer collet member 22 with a distal end of neck 56 in
abutment with the proximal end of inner collet member 26 and with a
proximal peripheral edge of the outer collet member 22 in abutment
with an external transverse shoulder at the junction of neck 56
with distal extension 51. The neck 56 is fixedly secured to the
outer collet member 22, such as adhesively, with the lumen or
internal passage of neck 56 longitudinally or axially aligned with
the internal passage of inner collet member 26. A passageway 57 in
the mid-section 53 extends longitudinally, proximally from end wall
54 in communication with the recess of distal extension 51.
Passageway 57 includes a forward passageway portion or part
longitudinally or axially aligned with the recess of distal
extension 51 and a rearward passageway portion or part having a
longitudinal axis disposed at a minimal acute angle with a
longitudinal axis of the forward passageway portion. According to a
preferred embodiment, the longitudinal axis of the rearward
passageway portion is disposed at an angle of 15.degree. to the
longitudinal axis of the forward passageway portion. The rearward
passageway portion of passageway 57 has an outlet along an external
surface of midsection 53 to establish communication with the
passageway 57 from externally of the handpiece body 12. The
rearward passageway portion of passageway 57 receives a distal end
of a suction tube 58. Suction tube 58, which is preferably made of
stainless steel, has a distal tube segment terminating distally at
the distal end received in passageway 57 and a proximal tube
segment terminating proximally at an open proximal end for being
coupled with a standard suction canister. The distal end of the
suction tube is secured in passageway 57, such as adhesively, with
the distal end of the suction tube located at the junction of the
forward passageway portion with the rearward passageway portion.
The distal segment of tube 58 is longitudinally or axially aligned
with the rearward passageway portion of passageway 57. The proximal
segment of tube 58 is disposed parallel with the forward passageway
portion of passageway 57 and has a plurality of truncated conical
configured barbs 59 adjacent the open proximal end thereof for
connection with the suction canister. As shown in FIG. 4, three
barbs 59 of increasing diametric size are arranged on tube 58 in
order of size with the diametrically smallest barb disposed closest
to the open proximal end of the suction tube. The recess of
proximal extension 52 has a uniform diameter forward recess section
and a uniform diameter rearward recess section, larger in diameter
than the forward recess section, longitudinally or axially aligned
with one another. An internal, transverse shoulder 60 is disposed
in the proximal extension 52 at the junction of the forward and
rearward recess sections. The transfer body 49 can have a plurality
of external oblong recesses as shown in FIG. 1, the recesses
extending part way through the thickness of the wall of the
transfer body to facilitate manual grasping or gripping of the
transfer body during use.
Drive unit 50, also shown in FIG. 4, includes a front drive shaft
61 disposed in the recess of distal extension 51 and a rear drive
shaft 62 disposed in the recess of proximal extension 52. Front
drive shaft 61, shown in FIG. 5, carries or is formed with a gear
63 and has a first cylindrical portion of uniform external diameter
extending distally from gear 63 and a second cylindrical portion of
uniform external diameter, smaller than the external diameter of
the first cylindrical portion, extending distally from the first
cylindrical portion in longitudinal or axial alignment therewith.
An external, transverse shoulder 64 is defined on the front drive
shaft 61 at the junction of the first and second cylindrical
portions. Gear 63 has an external diameter or size greater than the
external diameter of the first cylindrical portion and has a
plurality of gear teeth 65 parallel with a longitudinal axis of the
front drive shaft 61. A longitudinal bore 66 is formed entirely
through the front drive shaft 61 and includes a distal bore section
of uniform diameter extending part way through the second
cylindrical portion and a proximal bore section of uniform
diameter, smaller than the diameter of the distal bore section,
extending longitudinally, proximally from the distal bore section
through the remainder of the front drive shaft 61. A proximally
angled or sloping internal shoulder 67 is disposed in bore 66 at
the junction of the distal and proximal bore sections. A pair of
apertures are formed through the wall of the front drive shaft
close to a distal end thereof, the apertures being disposed at
180.degree. spaced locations about the longitudinal axis of front
drive shaft 61 to receive drive pins 68, respectively. Pins 68
protrude externally in a radial direction from the front drive
shaft 61 and have inner ends flush with an internal surface of the
second cylindrical portion of the front drive shaft 61 and rounded
outer ends spaced from an external surface of the second
cylindrical portion of drive shaft 61. The front drive shaft 61
including gear 63 is preferably made of stainless steel, and a
proximal face of gear 63 is highly polished for smoothness.
Rear drive shaft 62, as illustrated in FIGS. 6 and 7, carries or is
formed with a gear 69 and has a first cylindrical section of
uniform external diameter extending proximally from gear 69 and a
second cylindrical section of uniform external diameter, smaller
than the external diameter of the first cylindrical section,
extending proximally from the first cylindrical section in
longitudinal or axial alignment therewith such that an external
transverse shoulder 70 is defined at the junction of the first and
second cylindrical sections. Gear 69 is similar to gear 63 and has
a plurality of gear teeth 71 for mating with the gear teeth 65 in
driving engagement. Rear drive shaft 62 has an open proximal end
communicating with a longitudinal bore 72 extending distally from
the open proximal end to terminate at a conical end surface in the
second cylindrical section of the rear drive shaft. Opposed slots
73 are formed through the wall of the second cylindrical section of
rear drive shaft 62 at 180.degree. spaced locations about a
longitudinal axis of the rear drive shaft. Slots 73 communicate
with bore 72 and have open proximal ends communicating with the
open proximal end of the rear drive shaft and arcuate distal edges
disposed proximally of the conical end surface of bore 72. Slots 73
define a pair of opposed prongs 74 on rear drive shaft 62. Each
slot 73 has a distal portion of substantially uniform width and an
outwardly flared proximal portion of increasing width. Accordingly,
each prong 74 terminates proximally at a triangular configured tip
75. Slots 73 have a width between parallel side edges of the
prongs, and the width of the slots 73 is of a size to receive a
drive pin of motor assembly 14 as explained further below. The
parallel side edges of the prongs are parallel with the
longitudinal axis of the rear drive shaft, and the walls forming
the prongs are beveled interiorly along the tips 75. The rear drive
shaft 62 including gear 69 is preferably made of stainless
steel.
Front drive shaft 61 is disposed in the recess of the distal
extension 51 of transfer body 49 with the proximal surface of gear
63 adjacent end wall 54 and with the front drive shaft extending
into the neck 56 as shown in FIGS. 2 and 4. The bore 66 of front
drive shaft 61 is axially aligned with the forward portion of
passageway 57, which is disposed proximally of bore 66. A retaining
ring 76, such as a stainless steel Smalley retaining ring of
Smalley Steel Ring Co., Wheeling, Ill., is disposed on the second
cylindrical portion of the front drive shaft 61 distally of
external shoulder 64 and is secured in an internal groove or recess
formed in the distal extension 51. A pair of radial shielded
bearings 77 are mounted on the first cylindrical portion of front
drive shaft 61, and a washer spring 78 is disposed around the front
drive shaft 61 between retaining ring 76 and a distalmost bearing
77. A rotary seal 79 is disposed in an annular groove or recess
extending proximally a short distance from end wall 54 in
communication with the distal extension recess. Seal 79 is a
two-part seal including an O-ring 79A and an annular seal ring 79B
disposed between the O-ring 79A and the proximal surface of gear
63. The O-ring and seal ring are made of compressible materials;
and, preferably, the O-ring 79A is made of 5-148 EPR and the seal
ring 79B is made of mineral filled PTFE. The gear 63 is pre-loaded
against seal 79 such that the proximal surface of gear 63 is in
direct contact with the seal ring 79B and does not contact the end
wall 54. Accordingly, there is a small gap or space between the
proximal of gear 63 and the end wall 54 to eliminate metal to metal
contact.
The front drive shaft 61 is mounted for rotation within the
transfer body 49 with the drive pins 68 disposed in neck 56 for
being coupled with a hub of a hollow, tubular or cannulated
surgical blade which is to be driven by the drive unit 50. When a
blade is coupled to the front drive shaft 61, the lumen or hollow
interior of the blade and its hub will be longitudinally or axially
aligned with the bore 66 which, in turn, is longitudinally aligned
with the forward portion of passageway 57 such that bore 66 and
passageway 57 together define a continuous, substantially straight
suction channel in the handpiece body disposed proximally of the
blade for evacuating anatomical tissue cut by the blade from the
handpiece body 12. The suction channel is substantially straight;
that is, a substantial portion of the length of the suction channel
is linear and coaxial with the blade. Only the rearward passageway
portion of passageway 57, which accounts for a minimal portion of
the length of the suction channel in the handpiece body is disposed
at a minimal angle with the blade. The suction channel is therefore
coaxial or linear with the blade from the blade up to the distal
end of the suction tube 58. Accordingly, evacuation of tissue
through the blade and the handpiece body is along a straight path
up to the suction tube. Areas of turbulence in the suction channel
are minimized such that the potential for evacuated material to
become clogged within the handpiece is eliminated or greatly
minimized.
As shown in FIGS. 2 and 4, rear drive shaft 62 is disposed in the
recess of proximal extension 52 with a distal surface of gear 69
spaced slightly from end wall 55 and with teeth 71 in driving
engagement with teeth 65. Prongs 74 are disposed in the rearward
recess section of the proximal extension 52. A pair of radial
shielded bearings 77' are mounted on the first cylindrical section
of rear drive shaft 62. A retaining ring 76', similar to retaining
ring 76, is disposed around the second cylindrical section of rear
drive shaft 62 proximally of external shoulder 70 and is fixedly
secured in an internal groove or recess formed in the proximal
extension 52. A washer spring 78', similar to spring 78, is
disposed around the rear drive shaft between a proximal most
bearing 77' and the retaining ring 76'.
The motor enclosure 20 is preferably made of stainless steel or
titanium and includes an elongate tubular member of uniform
external diameter having a tubular neck 80 of smaller external
diameter extending distally therefrom in longitudinal or axial
alignment as shown in FIG. 2. An internal shoulder 81 and an
external shoulder 82 are defined at the junction of neck 80 with
the elongate tubular member. Neck 80 is received in the rearward
recess section of proximal extension 52 with a distal end of neck
80 in abutment with the internal shoulder 60 of proximal extension
52 and with a proximal end of proximal extension 52 in abutment
with the external shoulder 82 of motor enclosure 20. Neck 80 is
secured to the transfer body 49, such as adhesively, and the prongs
74 of the rear drive shaft 62 are disposed within the neck 80 with
tips 75 thereof disposed distally of internal shoulder 81. The
motor enclosure 20 has an open proximal end circumscribed by a
smaller diameter, annular proximal rim and has an external thread
83 extending distally from the proximal rim. The motor enclosure 20
is longitudinally or axially aligned with the rear drive shaft 62
allowing motor assembly 14 to be coupled with the rear drive shaft
in driving engagement when the motor assembly is installed or
inserted into the motor enclosure 20 via the open proximal end
thereof. A slot or keyway 85, shown in FIG. 1, is formed in the
proximal end of the motor enclosure 20 for receiving a key or
protrusion of motor assembly 14 as explained further below. Keyway
85 has an oblong configuration with a central longitudinal axis
parallel to the longitudinal axis of rear drive shaft 62. Keyway 85
has an open proximal end and an arcuate distal edge. Keyway 85 is
aligned with the longitudinal axis of rear drive shaft 62; that is,
longitudinal central axes of keyway 85 and rear drive shaft 62 are
contained in the same plane and such plane contains the
longitudinal axis of the motor enclosure 20.
Motor assembly 14, as shown in FIG. 2, includes an elongate,
cylindrical motor housing 86, a motor 87, shown in FIG. 9, disposed
within the housing 86 and an electrical connector 88 electrically
connected with motor 87. Motor 87 includes a motor shaft 89
extending distally from a front end of motor housing 86 in
longitudinal or axial alignment therewith. As shown in FIGS. 2 and
8, a pair of cylindrical drive pins 90 protrude from the motor
shaft 89 in a radial direction at 180.degree. spaced locations
about a longitudinal axis of the motor shaft 89 for being received
in slots 73 in driving engagement with prongs 74. As shown in FIG.
9, the motor housing 86 has a diametrically enlarged, open rear end
with an internal thread for threaded connection to connector 88.
Motor 87 is preferably a three-phase, brushless, DC motor having
Hall Effect sensors, such as that of Harowe Servo Controls, Inc. of
West Chester, Pa.
The electrical connector 88 is illustrated in FIGS. 10-12 and
includes a backshell 91 having a cylindrical main body portion and
an externally threaded neck of smaller diameter extending distally
from the main body portion. The externally threaded neck has an
external size to be threadedly received by the internally threaded
rear end of the motor housing 86 as shown in FIG. 9. The main body
portion of backshell 91 has an external diameter or size that is
the same or substantially the same as the external diameter or size
of the rear end of motor housing 86 such that the backshell is
diametrically flush with the motor housing. A raised key or
protrusion 92 protrudes externally from the main body portion of
backshell 91, the key 92 extending longitudinally, distally from a
proximal peripheral edge of backshell 91. Key 92 has a
configuration and size to mate with keyway 85 of motor enclosure
20; however, the height of key 92 is less than the height of keyway
85 to allow a key of an installation device to be received in
keyway 85 simultaneously with key 92 as explained further below. A
longitudinal axis of key 92 is disposed transverse or perpendicular
to a common longitudinal axis of drive pins 90 such that the drive
pins 90 are aligned with slots 73 when key 92 is aligned with
keyway 85. Accordingly, key 92 and keyway 85 comprise an alignment
mechanism for ensuring proper alignment of the motor assembly in
the handpiece body. A cylindrical recess 93 is formed in the main
body of backshell 91, the recess 93 extending distally from the
proximal peripheral edge of the backshell to terminate at a base
wall 94 in the backshell main body. A semi-cylindrical polarizing
insert 95 is disposed in recess 93, the insert 95 extending
proximally from base wall 94 to terminate at a planar surface flush
with the proximal peripheral edge of the backshell main body
portion. Insert 95 has a diameter smaller than the diameter of
recess 93, and the insert 95 is disposed in the recess 93 with its
diameter aligned with the diameter of recess 93. Accordingly, there
is a semi-circumferential gap or space between a curved outer
surface of insert 95 and a curved inner surface of the wall forming
the backshell main body portion. A plurality of contacts 96 are
mounted in the backshell 91 and have distal ends protruding
longitudinally, distally from a forward surface of the backshell
neck. Some of the contacts 96 extend longitudinally through the
backshell 91 to terminate at proximal ends forming pins 97, and the
remaining contacts 96 extend longitudinally through the backshell
to terminate at proximal ends forming receptacles 98 to provide a
male/female connector. As shown in FIG. 12, ten contacts 96 are
arranged in the backshell 91 with five of the contacts 96 forming
receptacles 98 in polarizing insert 95, and the remaining five
contacts 96 forming pins 97 protruding proximally from base wall
94. Pins 97 are disposed in recess 93 in symmetrical or mirror
image arrangement with receptacles 98. The distal ends of contacts
96 are designed, such as with slots, to be soldered to wire leads
99 of motor 87 as shown in FIG. 9. The pins 97 and receptacles 98
are designed to accept a polarized plug of an electrical cord
assembly for connection to a power console for supplying
electricity to motor 87 as explained further below. According to a
preferred embodiment, connector 88 is a custom ERY-2C electrical
connector of LEMO USA.
The handpiece body 12 is preferably made of durable, medically
acceptable materials, such as stainless steel or hard coat anodized
aluminum or titanium, for example, capable of being sterilized to
medical standards, such as by steam or flash autoclaving, gas
sterilization and/or soaking in a disinfectant solution.
Accordingly, the handpiece body 12 is designed for repeated use.
The motor assembly 14 is removably installed in handpiece body 12
allowing the motor assembly 14 to be removed from the handpiece
body 12 prior to sterilization of the handpiece body and to be
reinstalled in the sterilized handpiece body 12 prior to use. The
motor assembly 14 can be non-sterile such that the motor assembly
is not subjected to sterilization procedures that would reduce the
reliability and/or life of the motor. According to a sterile
transfer method of the present invention, a non-sterile motor
assembly 14 is installed in the sterile handpiece body 12 without
contaminating the sterile handpiece body as explained below.
The motor assembly 14 is installed in the handpiece body 12 with
the key 92 of connector 88 disposed in the keyway 85 of motor
enclosure 20. Accordingly, the drive pins 90 will be disposed in
the slots 73 in driving engagement with prongs 74. The front end of
motor housing 86 will be in abutment with the internal shoulder 81
of the motor enclosure 20 and the connector backshell 91 will be
flush with the proximal rim of the motor enclosure 20.
The motor 87 is powered by a software controlled power console via
an electrical cord assembly 111 coupled with connector 88 and the
power console as shown in FIG. 13. Cord assembly 111 comprises a
length of shielded electrical cable or cord 113 having a first end
carrying a first plug 115 for being coupled with electrical
connector 88 and having a second end carrying a second plug P for
being coupled to the power console. Cable 113 can be designed in
many various ways and can include various types of shielded
electric cable, such as that of W. L. Gore & Associates, Inc.
of Phoenix, Ariz., having conductors for transmitting electricity
from the power console PC to the motor 87. As shown in FIG. 14,
plug 115 is designed as a male/female plug for being coupled with
electrical connector 88 and has a cylindrical forward end with a
planar end surface 117 for abutting base wall 94 of connector 88. A
polarizing recess 119 corresponding to polarizing insert 95 is
formed in the plug 115. A plurality of receptacles 121 are disposed
in the plug 115 corresponding to pins 97 of electrical connector
88, and a plurality of pins 123 are disposed in the polarizing
recess 119 corresponding to receptacles 98 of connector 88, the
receptacles 121 and pins 123 being electrically connected with
conductors of cable 113. Accordingly, the plug 115 can be plugged
into the electrical connector 88 with the polarizing insert 95 of
the connector received within the polarizing recess 119 of the plug
with the pins 97 of the connector disposed within the receptacles
121 of the plug and the pins 123 of the plug disposed within the
receptacles 98 of the connector. As shown in FIGS. 13 and 14, a
locking or retaining ring 125 is concentrically disposed over the
plug 115 and has an internal annular protrusion 127 disposed
proximally of an annular abutment 129 of plug 115. The locking ring
carries an internal seal 184 disposed proximally of protrusion 127
to keep out moisture. The locking ring 125, which is movable
longitudinally relative to plug 115, is rotatable relative to plug
115 and is internally threaded along a distal end thereof for
threaded engagement with the thread 83 of motor enclosure 20.
Accordingly, a circumferential or annular gap or space is disposed
between plug 1l5 and locking ring 125 for accommodating the
proximal end of the motor enclosure 20 when the locking ring is
threaded thereon. The cord assembly 111 is designed and constructed
to be sterilized, such as via steam autoclave, for example, to
medical standards for repeated use.
FIGS. 15-17 illustrate a reusable motor installation device 100 for
use in the sterile transfer method according to the present
invention. Motor installation device 100 is in the nature of a
funnel 100 including a flared or truncated conical head 102 having
a relatively wide inlet end and a relatively narrow outlet end
opposite the inlet end and a tubular neck 103 extending
longitudinally, centrally from the head 102 in communication with
the outlet end. The wall forming head 102 is exteriorly beveled or
angled at the junction of the head 102 with the tubular neck 103 to
define a planar end surface 104 parallel to a plane containing a
terminal circumferential or peripheral edge 105 at the inlet end of
head 102. The tubular neck 103 is concentrically arranged with the
head 102 and extends longitudinally therefrom to terminate at an
open, free end that is externally threaded or ribbed as shown at
106 in FIG. 15. A circumferential lip 107 is disposed at the
junction of head 102 with the neck 103, i.e. at the outlet end of
head 102, and a notch 108 is formed in the lip 107 such that the
lip is circumferentially broken or discontinuous. The lip 107
protrudes inwardly such that the outlet defined by lip 107 at the
outlet end of head 102 is diametrically or circumferentially
smaller than the lumen of neck 103. A key or protrusion, such as a
dowel pin 109 extends through the wall forming the neck in
longitudinal alignment with the notch 108. The key 109 is spaced
longitudinally from the notch 108 and protrudes into the lumen of
neck 103. The distance that key 109 protrudes into the neck 103 is
selected to allow keys 92 and 109 to be disposed in the keyway 85
simultaneously when the motor assembly 14 is inserted into the
handpiece body 12 through funnel 100 according to the sterile
transfer method explained further below. The distance that key 109
is spaced longitudinally from seal 107 is selected such that the
key 109 is disposed in the keyway 85 with the annular proximal rim
of the motor enclosure 20 in abutment with lip 107 when the funnel
is placed over the motor enclosure to install the motor
assembly.
The neck 103 has a plurality of slots 101 formed therein, the slots
101 being equally spaced about a longitudinal axis of funnel 100.
As shown in FIG. 18, four slots 101 are separated from one another
by triangular shaped bridge segments 110 of neck 103. As shown in
FIG. 15, slots 101 are spaced longitudinally from key 109, the
slots 101 being disposed between key 109 and the open free end of
neck 103. As shown in FIG. 19, a deformable O-ring 112 is
positioned externally over neck 103 to be received in slots 101.
When the O-ring is received in slots 101 as shown in FIGS. 15, 16
and 17, the O-ring is deformed to assume a somewhat square
configuration with segments 114 of the O-ring protruding into the
lumen of neck 103. Funnel 100 is made of a suitable medically
acceptable material, such as titanium or stainless steel, and is
capable of being sterilized along with O-ring 112 assembled
thereon, such as by flash autoclaving, gas sterilization and/or
soaking to medical standards for repeated use.
Prior to use, the funnel 100, electrical cord assembly 111 and the
handpiece body 12, without the motor assembly 14 received in the
motor enclosure 20, are medically sterilized such as via flash
autoclaving, gas sterilization and/or soaking. The thusly
sterilized components are handled by sterile operating personnel in
a sterile operating field prior to surgery. According to the
sterile transfer method, the handpiece body 12 is held with the
open proximal end of motor enclosure 20 facing upwardly, and the
neck 103 of funnel 100 is placed over the open proximal end of the
motor enclosure 20. The funnel 100 is rotated relative to the motor
enclosure 20 until the key 109 is aligned with the keyway 85. The
key 109 will then drop into the keyway 85 until the proximal rim of
the motor enclosure 20 is in abutment with the lip 107. The O-ring
segments 114 grip the handpiece body 12 and resist removal of the
funnel 100 from the handpiece body such that the funnel remains in
place on the handpiece body even if the handpiece body is turned
upside down. Accordingly, the funnel 100 will be locked in place on
the handpiece body 12 with the key 109 protruding part way into the
keyway 85. The non-sterile motor assembly 14, which is handled
separately by operating personnel who can be non-sterile, is
inserted, shaft end first, through the inlet end of funnel 100 and
is rotated until the key 92 on the electrical connector 88 is
aligned with the notch 108 in the lip 107. Accordingly, the key 92
will be aligned with the keyway 85, and the motor assembly 14 will
pass through the neck of funnel 100 into motor enclosure 20 since
the key 92 passes through the notch 108 and enters the keyway 85.
The drive pins 90 will enter the slots 73 in driving engagement
with prongs 74, the triangular shaped tips 75 of the prongs 74
providing a self-centering function to facilitate entry of the
drive pins 90 in the slots 73. The funnel 100 is then manually
withdrawn or removed from the handpiece body 12, overcoming the
gripping force of O-ring 112 such that the key 109 is withdrawn
from the keyway 85. The motor assembly 14 is now properly installed
within the handpiece body 12 without compromising the sterility of
the handpiece body.
Once the motor assembly 14 has been properly installed in the
handpiece body 12, the sterile plug 115 is plugged into the
electrical connector 88 with a press fit with the locking ring 125
disposed in a proximal longitudinal position relative to plug 115
to allow the polarizing insert 95 to enter the polarizing recess
119 causing pins 97 of the electrical connector to enter the
receptacles 121 of the plug and causing the pins 123 of the plug to
enter the receptacles 98 of the connector. The locking ring 125 is
then rotated in a first rotational direction relative to the plug
115 to threadedly engage the proximal end of the motor enclosure
20. As the locking ring 125 is threaded over the proximal end of
the motor enclosure, the locking ring is moved longitudinally,
distally relative to the plug 115 to a distal longitudinal
position. The locking ring is rotated and, therefore, is moved
longitudinally until the threads of the locking ring and the motor
enclosure, respectively, are fully engaged. The proximal end of the
motor enclosure 20 is then held between the plug 115 and the
locking ring 125, with the locking ring 125 preventing withdrawal
of the plug 115 from the connector 88 and, therefore, preventing
withdrawal of the motor assembly 14 from the handpiece body 12. The
plug P is plugged into the power console, which is utilized to
supply electric power to motor 87 to rotate motor shaft 89,
operation of the console being controlled by the surgeon such as
via a foot switch or pedal for the console or directly from the
console. Motor shaft 89 rotates rear drive shaft 62 which in turn
rotates front drive shaft 61 via gears 63 and 69. Front drive shaft
61 in turn rotates a surgical blade drivingly engaged therewith to
cut anatomical tissue. The front drive shaft 61 can be rotated via
the motor assembly for full rotational movement along 360.degree.
continuously in the same direction and/or for oscillatory
rotational movement in reverse directions along less than
360.degree..
FIG. 20 illustrates a surgical blade assembly 200 for use with the
handpiece 10. Blade assembly 200 includes an outer blade 202, a hub
204 mounting a proximal end of the outer blade, an inner blade 206
for being disposed in the outer blade with the inner blade passing
through hub 204, and a hub 208 mounting a proximal end of the inner
blade. Outer blade 202 includes an elongate tubular member having
an open proximal end and an open distal end or tip 210 carrying a
cutting edge 212. As shown in FIG. 21, hub 204 for outer blade 202
includes a forward hub part 214 and a rearward hub part 216.
Forward hub part 214 includes a distal cylindrical main body
portion tapering to a smaller external diameter proximal
cylindrical portion. A longitudinal passage 218 extends entirely
through the forward hub part 214 and includes a forward passage
section of uniform diameter, an intermediate passage section of
uniform diameter greater than the diameter of the forward passage
section, and a rearward passage section of uniform diameter greater
than the diameter of the intermediate passage section. An internal
transverse shoulder 220 is defined at the junction of the
intermediate and rearward passage sections, and an annular seal 222
is disposed in the passage 218 in abutment with shoulder 220. An
angular extension 224 protrudes angularly, proximally from the
forward hub part 214 and has a longitudinal passage extending
entirely therethrough in communication with the passage 218.
Extension 224 has an open free end formed with a barb 226 for being
coupled with an irrigation supply tube. Rearward hub part 216
includes a distal cylindrical section, a proximal cylindrical
section having an external diameter greater than the diameter of
the distal cylindrical section and an annular flange 228 disposed
between the distal and proximal cylindrical sections. A
longitudinal passage 230 of uniform diameter extends entirely
through the rearward hub part 216. A plurality of partial spherical
recesses 232 are formed along an outer forward edge or corner of
flange 228 at 30.degree. spaced locations about a longitudinal axis
of rearward hub part 216. The rearward hub part 216 is assembled to
the forward hub part 214 with the distal cylindrical section of the
rearward hub 216 part secured in the rearward passage section of
the forward hub part 214 with a distal end of the rearward hub part
216 in abutment with seal 222. The distal section of the rearward
hub part can be secured in the rearward passage section of the
forward hub part in many various ways, such as adhesively. With the
rearward hub part 216 assembled to the forward hub part, the
passages 218 and 230 are longitudinally or axially aligned to form
a continuous longitudinal passage through hub 204. The open
proximal end of the outer blade 202 is secured, such as adhesively,
in the forward passage section of the forward hub part 214 with the
lumen or internal passage of the outer blade 202 longitudinally or
axially aligned with the passage through hub 204. A hole or
aperture is formed in the outer blade 202 in alignment with the
longitudinal passage of angular extension 224 to establish
communication between the passage of the angular extension and the
lumen of outer blade 202.
Inner blade 206 is illustrated in FIG. 22 and includes an elongate
tubular member having an open proximal end 233 and an open distal
end or tip 234 carrying a cutting edge 236 designed to cooperate
with cutting edge 212 to cut anatomical tissue. Hub 208 for inner
blade 206 includes a cylindrical body having a passage 238
extending longitudinally entirely therethrough. Passage 238 has a
forward passage portion and a rearward passage portion larger in
diameter than the forward passage portion. An internal transverse
shoulder 240 is defined at the junction of the forward and rearward
passage portions. As shown in FIGS. 22 and 23, a plurality of
oblong slots 242 are formed in a proximal end of hub 208 at
90.degree. spaced locations about a longitudinal axis of hub 208
with the slots 242 extending longitudinally, parallel to the
longitudinal axis of hub 208 to define prongs 244. Each slot 242
has a distal portion of uniform width and a proximal portion of
increasing width in the proximal direction. Accordingly, the
proximal portions of slots 242 flare out from the distal portions
thereof such that the prongs 244 have triangular shaped tips 246,
the prongs 244 being similar to the prongs 74. The hub 208 and the
prongs 244 are designed to be disposed in the handpiece 10 with the
drive pins 68 of the front drive shaft 61 disposed in a pair of
opposed slots 242 in driving engagement with prongs 244. An annular
or cylindrical seal 248 is disposed within passage 238 at a
proximal end of groove 249 along a forward surface thereof. A coil
spring 250 is concentrically disposed in passage 238 and is mounted
in compression between shoulder 240 and seal 248 with an end of the
spring 250 being disposed in the groove 249. The open proximal end
233 of the inner blade 206 is disposed in the passage 238 to
terminate proximally of seal 248 and is secured, such as
adhesively, in passage 238 with the inner blade passing
concentrically through spring 250. Preferably, the blades are made
of stainless steel and the hubs are made of plastic, such as ABS
resin, for disposability or single patient use.
The outer blade 202 is assembled with the inner blade 206 as shown
in FIG. 20 with the inner blade 206 passing through hub 204 to
align the cutting edges 212 and 236 and with hub 208 disposed
proximally of hub 204. The inner blade 206 is of a size to be
closely received within outer blade 202 and hub 204 while allowing
the inner blade to be rotated relative to the outer blade to move
the cutting edge 236 past the cutting edge 212 to cut anatomical
tissue. The blade assembly 200 is coupled with the handpiece 10 by
moving the middle collet member 24 longitudinally, proximally
relative to the outer collet member 22 to the retracted position
causing ball bearings 47 to be aligned with the forward passage
segment of the middle collet member. The hubs 204 and 208 are
introduced through the aperture 44 in the middle collet member 24
and are moved longitudinally to enter the passage of the inner
collet member 26 such that the drive pins 68 of the front drive
shaft 61 enter the slots 242 of hub 208, the triangular tips 246 of
prongs 244 providing a self-centering function facilitating entry
of the drive pins 68 into a pair of opposed slots 242. Flange 228
enters the passage of the inner collet member 26, causing the ball
bearings 47 to be moved outwardly from holes 46. With the hubs 204
and 208 fully inserted in the handpiece 10, a proximal surface of
flange 228 will be in abutment with internal shoulder 45, and the
partial spherical recesses 232 will be in alignment with holes 46.
The middle collet member 24 is released, causing the middle collet
member to be returned to the extended position due to the bias of
spring 48. Return of the middle collet member to the extended
position causes the ball bearings 47 to be moved inwardly into
holes 46 and the partial spherical recesses 232 aligned therewith.
Accordingly, flange 228 of hub 204 is prevented from moving
distally and rotationally by ball bearings 47 and is therefore
locked in place within the handpiece 10. The hub 208 cannot enter
the rearward hub 204; and, accordingly, the hub 208 is also locked
in place within the handpiece 10. The extension 224 of hub 204 is
connected with an irrigation supply tube for supplying irrigation
fluid between the outer blade and the inner blade, the seal 222
preventing egress of irrigation fluid proximally therepast. The
spring biased seal 248 of hub 208 allows some tolerance between the
hub 208 and the front drive shaft 61 to maintain proper alignment
therewith. Preferably, the blade assembly is provided in a sterile
condition for single patient use and; since the seals 222 and 248
are disposed in the hubs 204 and 208, respectively, and not in the
handpiece, they are not subjected to the rigors of medical
resterilization. With the blade assembly 200 coupled with the
handpiece 10, rotation of the front drive shaft 61, as controlled
by the power console, causes the inner blade 206 to be rotated
within and relative to the outer blade 202 to move cutting edge 236
past cutting edge 212 to cut anatomical tissue through the open
distal ends of the blades. Irrigating fluid is supplied at the
cutting tips 210 and 234 via extension 224 and the lumen of outer
blade 202, such fluid passing through the hole or aperture in the
outer blade to flow between the inner and outer blades. Anatomical
tissue cut by the blades will be aspirated or evacuated through the
inner blade member 206 and the handpiece 10 for collection in the
suction canister coupled with suction tube 58. The seal 79 prevents
material being evacuated from crossing the seal to gears 63 and
69.
FIG. 25 illustrates at 379 an alternative seal forming a seal with
the proximal surface of the gear of the front drive shaft. Seal 379
is disposed in an annular groove or recess of transfer body 49 and
includes an annular seal member 379A having a U-shaped
configuration in cross-section with spaced legs 380A and an annular
spring 379B disposed between legs 380A. The space between legs 380A
is disposed along an outer periphery of the seal member 379A to
receive spring 379B, which has an oblong configuration in
cross-section. A forward surface of seal member 379A is in contact
with the proximal surface of gear 63 such that there is a small air
gap between the proximal surface of the gear and the transfer body
49. Seal 379 functions similar to seal 79 in that the gear 63 is in
contact with the seal member 379A and does not contact the transfer
body 49, and the seal 379 prevents material evacuated from the
handpiece from moving therepast.
FIG. 25 illustrates a lip seal 400 for use on the front and rear
drive shafts. Lip seal 400 includes an annular seal member or ring,
preferably made of compressible, deformable material, disposed
around front drive shaft 61 between retaining ring 76 and bearings
77. Seal 400 has a slightly protruding proximal peripheral edge
adjacent the distalmost bearing 77. Seal 400 can be used in place
of the washer spring, or the seal 400 can be used in conjunction
with a spring, such as a garter spring, a spring being shown within
the seal 400 in dotted lines at 478. Although the seal 400 is
illustrated on the front drive shaft 61, it should be appreciated
that a seal 400 can be disposed on the rear drive shaft between the
retaining ring and the proximalmost bearing in the same manner as
described for the front drive shaft 61.
The handpiece of the present invention is relatively small and
lightweight providing many functional benefits for the ENT surgeon
as well as other medical specialities. The handpiece can be used
with many various interchangeable blades having different cutting
tips in accordance with a procedure to be performed. Tissue cut by
the blades is evacuated through the handpiece in a substantially
in-line or straight path while maintaining a small profile for the
handpiece. Since tissue is evacuated along a straight path through
the handpiece up to the suction tube, which itself is at a minimal
angle, areas of turbulence in the suction channel are reduced such
that clogging of tissue in the handpiece body is eliminated or
greatly minimized. The reliability and/or life of the motor
assembly is greatly increased since the motor assembly is removed
prior to sterilization of the handpiece body for reuse and is
reinstalled in the sterilized handpiece body prior to surgery
without contaminating the handpiece body. Removability of the motor
assembly allows various different motor assemblies with different
operating speeds and features to be installed in the handpiece in
accordance with optimal procedural use. The handpiece according to
the present invention can be powered off of its own power console
or the existing power consoles of various manufacturers by
orienting the output signals of the power consoles for
compatibility with the handpiece or by utilizing a motor assembly
and/or cord assembly compatible with the power consoles.
Other objects and advantages of the present invention will become
apparent from the following description of the preferred
embodiments taken in conjunction with the accompanying drawings,
wherein like parts in each of the several figures are identified by
the same reference characters.
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